The present invention relates to a system for monitoring data related to disk storage drive performance. More particularly, the invention relates to a system which measures the throughput performance of a disk storage drive.
In recent years, hard disk drives (HDDs) have been developed which can predict HDD errors. These HDDs monitor various performance criteria, including the number of times the HDD motor has been started and stopped, and the length of time the HDD has had a supply of electric power. As a result, most HDDs can notify a host system, such as a personal computer, regarding potential HDD errors.
Another performance criterion that is commonly monitored in an HDD is throughput performance. Throughput performance is defined as the time the HDD requires to read data from the data-recording surface of the disk. The CPU incorporated in the HDD compares the time spent to read data from the data-recording surface of the disk (the "actual throughput performance") with a reference time (the "theoretical throughput performance"). The overall performance of the HDD over a period of time can be determined by monitoring the difference between actual throughput performance and theoretical throughput performance.
The time required to read data from the HDD may vary depending on several factors, including: (1) the seek operation, in which the read/write head of the HDD moves to a target position in the disk; and (2) the number of times the head attempts to read data from the disk, which in turn, may be affected by the presence of defects on the data-recording surface of the disk. The lower the speed of the seek operation, or the greater the number of data-reading attempts, the longer the time the HDD requires to read data from the disk.
The present way of measuring throughput performance is time-consuming because the entire data-recording surface of the disk has to be read before the throughput performance can be measured. In order to shorten the time for measuring throughput performance, one may read only a part of the data-recording surface of the disk. However, defects in other parts of the data-recording surface will not be reflected in such a measurement. Thus, there is a need for a system that measures throughput performance efficiently and accurately.